Multi-factor authentication for virtual reality

ABSTRACT

Authenticating for a virtual reality (VR) system using a plurality of factors of authentication, including: collecting a password entered into a virtual keyboard for a first factor of the plurality of factors of authentication, wherein the password is entered by a user selecting a series of data including numbers, letters, or images on the virtual keyboard displayed on a display of the VR system; and collecting a biometric fingerprint from movements of the VR system for a second factor of the plurality of factors of authentication.

BACKGROUND Field

The present disclosure relates to a virtual reality (VR) system, andmore specifically, to multi-factor authentication for the VR system.

Background

Since virtual reality (VR) is spreading, some VR applications may accesssensitive or confidential information in the future. Thus, in thefuture, more robust authentication may be required.

Currently, most VR systems use a virtual keyboard displayed in ahead-mounted display (HMD) to enter digital information. In thesesystems, the user activates the keyboard using either hand gesturerecognition with data gloves or a wand pointing to the displayed keys.However, these types of user interfaces are complicated and cumbersome.

SUMMARY

The present disclosure provides for a multi-factor authentication suitedfor the VR system using the head-mounted display (HMD).

In one implementation, a method of authenticating for a VR system usinga plurality of factors of authentication is disclosed. The methodincludes: collecting a password entered into a virtual keyboard for afirst factor of the plurality of factors of authentication, wherein thepassword is entered by a user selecting a series of data includingnumbers, letters, or images on the virtual keyboard displayed on adisplay of the VR system; and collecting a biometric fingerprint frommovements of the VR system for a second factor of the plurality offactors of authentication.

In one implementation, the VR system is a head-mounted display (HMD). Inone implementation, the method further includes displaying the virtualkeyboard on a half sphere in a fixed position within the half sphere. Inone implementation, the virtual keyboard is arranged as a random displayof at least ten keys on the half sphere. In one implementation, thepassword is entered by gazing in a direction of a button on the virtualkeyboard to select the button. In one implementation, the selectedbutton is validated by making a pre-defined acknowledging head gesture.In one implementation, selection of the selected button is removed bymaking a pre-defined unselecting head gesture. In one implementation,the biometric fingerprint is collected from the movements of the VRsystem as reflected in the pre-defined acknowledging head gesture andthe pre-defined unselecting head gesture. In one implementation,collecting the biometric fingerprint includes: measuring accelerationsof the pre-defined acknowledging head gesture and the pre-definedunselecting head gesture; and normalizing the accelerations. In oneimplementation, the method further includes comparing the collectedbiometric fingerprint to fingerprints in a fingerprint database; andidentifying the user when a fingerprint match is made. In oneimplementation, the fingerprint match means that a similarity of thecollected biometric fingerprint and a reference fingerprint of thefingerprint match are within a defined boundary.

In another implementation, a system of authenticating for a VR systemusing a plurality of factors of authentication is disclosed. The systemincludes: a first factor of authentication collector configured tocollect a password entered into a virtual keyboard, wherein the passwordis entered by a user selecting a series of data including numbers orimages on the virtual keyboard displayed on a display of the VR system;and a second factor of authentication collector configured to collect abiometric fingerprint from movements of the VR system.

In one implementation, the VR system is a head-mounted display (HMD). Inone implementation, the system further includes a projector configuredto display the virtual keyboard on a half sphere in a fixed positionwithin the half sphere. In one implementation, the virtual keyboard isarranged as a random display of at least ten keys on the half sphere. Inone implementation, the second factor of authentication collector isconfigured to collect the biometric fingerprint from the movements ofthe VR system as reflected in pre-defined head gestures. In oneimplementation, the second factor of authentication collector collectsthe biometric fingerprint by measuring accelerations of the pre-definedhead gestures. In one implementation, the system further includes acomparator configured to compare the collected biometric fingerprint tofingerprints in a fingerprint database; and an identifier configured toidentify the user when a fingerprint match is made.

In yet another implementation, an apparatus for authenticating for a VRsystem using a plurality of factors of authentication is disclosed. Theapparatus includes: a first means for collecting a password entered intoa virtual keyboard for a first factor of the plurality of factors ofauthentication, wherein the password is entered by a user selecting aseries of data including numbers or images on the virtual keyboarddisplayed on a display of the VR system; and a second means forcollecting a biometric fingerprint from movements of the VR system for asecond factor of the plurality of factors of authentication.

In one implementation, the second means for collecting collects thebiometric fingerprint from the movements of the VR system as reflectedin pre-defined head gestures. In one implementation, the second meansfor collecting collects the biometric fingerprint by measuringaccelerations of the pre-defined head gestures.

Other features and advantages should be apparent from the presentdescription which illustrates, by way of example, aspects of thedisclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The details of the present disclosure, both as to its structure andoperation, may be gleaned in part by study of the appended drawings, inwhich like reference numerals refer to like parts, and in which:

FIG. 1 is a layout of a virtual keypad displayed on a sphere inaccordance with one implementation of the present disclosure;

FIG. 2 is a layout of the virtual keypad displayed on the sphere butprojected in a polar coordinate in accordance with one implementation ofthe present disclosure;

FIG. 3 is a flow diagram illustrating a process for detecting phases inaccordance with one implementation of the present disclosure;

FIG. 4 is a flow diagram illustrating a process for detecting anacknowledging head gesture in accordance with one implementation of thepresent disclosure;

FIG. 5 is a flow diagram illustrating a process for authenticating for aVR system using a plurality of factors of authentication in accordancewith one implementation of the present disclosure; and

FIG. 6 is a block diagram illustrating a system for authenticating for aVR system using a plurality of factors of authentication in accordancewith one implementation of the present disclosure.

DETAILED DESCRIPTION

As described above, current virtual reality (VR) systems may usecomplicated and cumbersome user interfaces.

Certain implementations of the present disclosure provide for amulti-factor authentication suited for the VR system using thehead-mounted display (HMD). For example, the multi-factor authenticationuses at least two of: (1) something the user knows, e.g., a password;(2) something the user owns, e.g., a mobile phone or physical token; and(3) something the user is, e.g., the user's fingerprints, voice, orcharacteristic motions. In one implementation, a fingerprint may includea biometric signature. After reading these descriptions, it will becomeapparent how to implement the disclosure in various implementations andapplications. Although various implementations of the present disclosurewill be described herein, it is understood that these implementationsare presented by way of example only, and not limitation. As such, thisdetailed description of various implementations should not be construedto limit the scope or breadth of the present disclosure.

In one implementation, the multi-factor authentication includes enteringa password and collecting a biometric fingerprint, while wearing theHMD. For example, the user enters a password by watching a sequence ofkeys to select a series of data such as numbers, letters, symbols,and/or images on the virtual keyboard displayed in the HMD. Thebiometric fingerprint can be collected by monitoring the movement of thesystem, such as as HMD movement (which represents the movement of theuser's head) or movement of the user, such as hand or body movement(e.g., captured by a camera).

In a particular implementation of the first factor authentication (i.e.,entering the password), following steps may be taken after a user putson an HMD. Initially, an application of a VR system displays in the HMD,a virtual keyboard. For example, a numerical keypad for entering thepersonal identification number (PIN) may be displayed in the HMD.

FIG. 1 is a layout 100 of a virtual keyboard or keypad displayed on asphere in accordance with one implementation of the present disclosure.In this implementation, the virtual keypad (which may be configured asan ordered keyboard or random display of numbers) is in a fixed positionwithin the sphere on which the HMD displays and the user views thekeypad. In one implementation, a six-digit PIN may be used as thepassword. Thus, the application displays a keypad of ten buttons in thehalf-sphere in front of the user. The order of the ten buttons israndomized.

In one implementation, to select a key on the keypad for entering thepassword, the user moves the head in the direction of the button (or keyor other displayed virtual items). The button that is gazed by the useris then highlighted as the selected button. The user validates theselected button by making a predefined acknowledging head gesture suchas a vertical nod. The highlighting of the selected button may beremoved by a predefined unselecting head gesture such as a horizontalnod. Thus, the user enters the password with a succession of gazing tothe key to be selected and acknowledging/unselecting with head gestures.

In one implementation, for security reasons, the layout of the virtualkeypad is at least randomized for each new entry of the password. Thus,the randomization of the layout prevents leakage of the password (bywatching the head movements) to the unauthorized persons. In someimplementations, the layout may even be randomized after each keyselection to prevent the leakage of the information (i.e., thepassword). In another implementation, the password is a sequence ofpictograms to be spotted in a landscape rather than alphanumericalcharacters.

In a particular implementation of the second factor authentication(i.e., the biometrics), the application of the VR system measures thebiometrics to generate the biometric fingerprint. As for gait ormanuscript signatures, the movements of the user's head for a knowngesture are unique to the user. For example, the acknowledging headgesture and the unselecting head gesture may serve that purpose. In oneimplementation, the biometrics is measured as acceleration projected ontwo axes of the head for both the acknowledging and unselectinggestures. Once normalized, the parameters (e.g., the acceleration) ofthe gestures form a unique biometric fingerprint.

In biometrics systems, an initial registration phase records severalinstances of the gestures or movements. For the initial registrationphase, the user repetitively performs the acknowledging head gesture andthe unselecting head gesture. Thus, the registration phase normalizesthe entries and averages them to generate a reference fingerprint.During selection of the keys, the application records the successivelycaptured biometric fingerprint.

In one implementation, the application of the VR system has access to afingerprint database. For each registered user, the fingerprint databaseholds a record that includes a user ID (which identifies the userunambiguously) and the reference fingerprint of the user. In oneimplementation, the reference fingerprint is a series of dataAR_(j)={δx_(j), δy_(j)}, where δx represents azimuth acceleration and δyrepresents elevation acceleration. This series is defined after atypical biometrics registration phase, wherein the user performs severalacknowledging head gestures and the registration performs normalizationand statistics calculation to extract the “average” fingerprint for theuser.

To authenticate the user, the application may verify two conditions: (1)the password entered via the virtual keypad matches the password of theuser; and (2) at least one of the measured biometric fingerprintsmatches the reference fingerprints of the user (i.e., the user isvalidated). In one implementation, the fingerprint match means that thesimilarity of the measured biometric fingerprint and the referencefingerprint are within a defined boundary.

FIG. 2 is a layout 200 of the virtual keypad displayed on the sphere butprojected in a polar coordinate in accordance with one implementation ofthe present disclosure. The horizontal axis (i.e., the x-axis)represents the azimuth, whereas the vertical axis (i.e., the y-axis)represents the elevation. The origin is the direction of the HMD whenstarting the authentication process.

In one implementation, each displayed button or key (i.e., K_(i)) isrepresented by a triplet, K_(i)={x_(i), y_(i), V_(i)}, where: x_(i)represents the azimuth of the center of the displayed key in degrees andx_(i)∈]−90, 90[; y_(i) represents the elevation of the center of thedisplayed key in degrees and y_(i)∈]−90, 90[; and V_(i) represents thevalue of the key and V_(i)∈{0 . . . 9}. Thus, in the illustratedimplementation of FIG. 2, K₁={0, 30, 0} and K₄={−60, 0, 6}.

In one implementation, the HMD periodically reports the direction of theuser's head (i.e., the gaze) to the application in the form of polarcoordinates, {x_(user), y_(user)}. Thus, initially, the applicationdetermines that the user is looking at K_(i) if both conditions inEquation [1] are true.

$\begin{matrix}\left\{ {\begin{matrix}{{{x_{user} - x_{i}}} \leq R} \\{{{y_{user} - y_{i}}} \leq R}\end{matrix},} \right. & \lbrack 1\rbrack\end{matrix}$

where R represents a fixed value. In one implementation, value R is theradius of the circle encompassing the key.

In one implementation, the process of selecting a key is as describedbelow.

First, when the application determines that the user is watching orgazing at a key (i.e., Equation [1] is satisfied for one value of i),the application graphically highlights the gazed key. When the usergazes away from the key (i.e., Equation [1] is no longer met for thecorresponding value of i), then the application removes the highlight.

Second, if the key is highlighted for a given period of time (e.g., 100mS), then the application enters the head gesture detection mode havingthree sub-modes. In the first sub-mode, if the acknowledging headgesture is detected, then the application records the key selection byusing the value V_(i). Visible information and audible signal may informthe user of the key selection. The application also records the measuredbiometric fingerprint. In the second sub-mode, if the unselecting headgesture is detected, then the application removes the highlight of theselected key. In the third sub-mode, if no known gesture is detected,then the application removes the current highlight.

In one implementation, the password acquisition process waits for theuser to select a predetermined number of keys (e.g., after six keys areselected). Once the predetermined number of keys is selected, theapplication enters the authentication verification phase.

In another implementation, the HMD is configured with an eye-gaze oreye-movement tracking system that registers the direction of theeye-gaze or eye-movement in the visor rather than the position of theHMD. In this implementation, the coordinates {x_(user), y_(user)} are acombination of the position of the HMD and the direction of theeye-gaze. Thus, this implementation allows a selection of the key withless head movements. This may be especially useful for relatively largekeyboards (e.g., larger than numerical keypads with ten keys). In thisimplementation, only the acceleration of the HMD is used to derive themeasured biometric fingerprint (i.e., the eye tracking information isnot used to derive the measured biometric fingerprint).

In one implementation, in detecting head gestures, the vertical nod ofthe user's head is considered an acknowledging head gesture, while thehorizontal node is considered an unselecting head gesture.

In one implementation, to detect a head gesture, the application recordsthe acceleration of the head in the polar coordinate system every nmilliseconds during a predetermined number of seconds. Thus, theapplication has a series of samples A_(j)={δx_(j), δy_(j)}, where δx_(j)represents the azimuth acceleration during the interval j, and δy_(j)represents the elevation acceleration during the same interval j.

In one implementation, the process of detecting the acknowledging headgesture and the unselecting head gesture may be divided into fourphases. For example, Phase 1 represents a pause in which the HMD is“still” (which means that the user does not move perceptibly). Phase 2represents the movement in a first direction (e.g., up or down for theacknowledging head gesture, and right or left for the unselecting headgesture). Phase 3 represents the movement in a second direction that isin reverse from the first direction (i.e., if the first direction is up,then the second direction is down, if the first direction is right, thenthe second direction is left, and vice versa). Phase 4 represents apause in which the HMD is “still”.

In one implementation, a set of parameters (listed below) characterizesthe above-described phases.

-   -   ε_(still)=threshold of acceleration for a pause.    -   ε_(move)=threshold of acceleration for a nod.    -   Δ_(still)=minimal duration of a pause (i.e., Phases 1 & 4). The        unit of this parameter (Δ_(still)) is the number of measurement        periods. Thus, the actual minimal duration of a pause is        Δ_(still)×n milliseconds    -   Δ_(mov1)=minimal duration of first movement (i.e., Phase 2).    -   Δ_(mov2)=minimal duration of second movement (i.e., Phase 3).    -   Δ_(max)=maximum duration of each phase (i.e., if a phase is not        completed within Δ_(max)×n milliseconds, then the phase failed).

A sample A_(j) belongs to one of the following categories; still, up,down, right, left or bad. The following set of equations defines thecategorization:

$\begin{matrix}{A_{j}\left\{ \begin{matrix}{{{{\delta \; x_{j}}} < ɛ_{still}},\ {\left. {{{\delta \; y_{j}}} < ɛ_{still}}\rightarrow{Cat} \right.\  = {still}}} \\{{{{\delta \; x_{j}}} < ɛ_{still}},\ {\left. {{\delta y_{j}} > ɛ_{mov}}\rightarrow{Cat} \right.\  = {up}}} \\{{{{\delta \; x_{j}}} < ɛ_{still}},\ {\left. {{{- \delta}y_{j}} > ɛ_{mov}}\rightarrow{Cat} \right.\  = {down}}} \\{{{{\delta \; y_{j}}} < ɛ_{still}},\ {\left. {{\delta x_{j}} > ɛ_{mov}}\rightarrow{Cat} \right.\  = {right}}} \\{{{{\delta \; y_{j}}} < ɛ_{still}},\ {\left. {{{- \delta}x_{j}} > ɛ_{mov}}\rightarrow{Cat} \right.\  = {left}}} \\{{{{\delta \; x_{j}}} > ɛ_{mov}},\ {\left. {{{\delta \; y_{j}}} > ɛ_{mov}}\rightarrow{Cat} \right. = {bad}}}\end{matrix} \right.} & \lbrack 2\rbrack\end{matrix}$

Once the parameters are defined as described above, the followingprocess defines a successful or failed completion of a phase.

FIG. 3 is a flow diagram illustrating a process 300 for detecting phasesin accordance with one implementation of the present disclosure. In oneimplementation, the process 300 verifies whether there are Δ_(mov)successive samples that are of the expected category, at block 302. ForPhase 1 and Phase 4, the category is still, and Δ_(mov)=Δ_(still). ForPhase 2, the category is down for the acknowledging head gesture andright for the unselecting head gesture, and Δ_(mov)=Δ_(mov1). For Phase3, the category is up for the acknowledging head gesture and left forthe unselecting head gesture, and Δ_(mov)=Δ_(mov2). If there are notenough successive samples, then the detection fails, at block 316.

If there are enough samples, then the process waits until a sample hasan unexpected category, at block 324, or the total number of analyzedsamples reaches the threshold Δ_(max), at block 330. In the first case(i.e., there is an unexpected category where the user initiates another“movement”, for example, from up to down), the detection is successful,at block 326. In the second case (i.e., the user stayed a long time inthe same category, for example, a long pause), the detection issuccessful but too long, at block 332.

In a particular implementation, initially, counter1 and counter2 areboth set to 0, at block 310. A sample is acquired, at block 312, and adetermination is made, at block 314, whether the sample is a propercategory. If the sample is not the proper category, then the detectionfails, at block 316. Otherwise, if the sample is the proper category,then the both counters counter 1 and counter2 are increase, at block318. A determination is the made, at block 320, whether counter1 lessthan Δ_(mov). If counter1 is less than Δ_(mov), the more sample isacquired, at block 312. Otherwise the sample is acquired, at block 322,to determine, at block 324, whether the acquired sample is an unexpectedcategory, or the total number of analyzed samples has reached thethreshold Δ_(max). If it is determined, at block 324, that the acquiredsample is an unexpected category, then the detection is declaredsuccessful, at block 326. Otherwise, if it determined, at block 324,that the acquired sample is a proper category, then counter2 isincreased, at block 328. A determination is then made, at block 330,whether the total number of analyzed samples has reached the threshold(i.e., counter2<Δ_(max)). If the total number of samples has reached thethreshold, the detection is declared successful but too long, at block332. Otherwise, another sample is acquired, at block 322.

FIG. 4 is a flow diagram illustrating a process 400 for detecting anacknowledging head gesture in accordance with one implementation of thepresent disclosure. The process 400 describes a series of phasedetecting steps.

In the illustrated implementation of FIG. 4, the process 400 attempts todetect phase 1 by determining, at block 410, that the duration of themovement (Δ_(mov)) should be equal to or greater than the minimalduration for a pause (Δ_(still)), wherein the expected category is“still” (phase 1). Then, the phase 1 detection is performed, at block412. If the phase detection fails, at block 420, the phase detection isdeclared failed, at block 422, which means that the user's head hasmoved. If it is determined, at block 424, that the phase detection was asuccess but the duration of the pause was too long, the detection iscontinued, at block 412, until proper phase 1 is determined, at block424.

In the illustrated implementation of FIG. 4, once phase 1 has beendetected, the process 400 attempts to detect phase 2 (i.e., the user'shead moving down) by determining, at block 430, that the duration of themovement (Δ_(mov)) should be equal to or greater than the minimalduration for the first movement (Δ_(mov1)), wherein the expectedcategory is “down” (phase 2). Then, the phase 2 detection is performed,at block 432. If the phase detection fails, at block 434, the overalldetection is declared failed and the key is deselected, at block 436. Ifit is determined, at block 438, that the phase detection was a successbut the duration of the first movement (Δ_(mov1)) was too long, then theoverall detection is declared failed and the key is deselected, at block456.

In the illustrated implementation of FIG. 4, once phase 2 has beendetected, the process 400 attempts to detect phase 3 (i.e., the user'shead moving up) by determining, at block 440, that the duration of themovement (Δ_(mov)) should be equal to or greater than the minimalduration for the second movement (Δ_(mov2)), wherein the expectedcategory is “up” (phase 3). Then, the phase 3 detection is performed, atblock 442. If the phase detection fails, at block 444, the overalldetection is declared failed and the key is deselected, at block 446. Ifit is determined, at block 448, that the phase detection was a successbut the duration of the second movement (Δ_(mov2)) was too long, thenthe overall detection is declared failed and the key is deselected, atblock 456.

In the illustrated implementation of FIG. 4, once phase 3 has beendetected, the process 400 attempts to detect phase 4 (i.e., the userstayed still) by determining, at block 450, that the duration of themovement (Δ_(mov)) should be equal to or greater than the minimalduration for the pause (Δ_(still)), wherein the expected category is“still” (phase 4). Then, the phase 4 detection is performed, at block452. If the phase detection fails, at block 454, the overall detectionis declared failed and the key is deselected, at block 456. If it isdetermined, at block 454, that the phase detection was a successregardless of its length, then the overall detection is declared asuccess, at block 458.

The illustrated implementation of FIG. 4 can be extended to a secondprocess for detecting an unselecting head gesture. Thus, in the secondprocess, phases 2 and 3 would use the parameters for horizontal noddinginstead of the vertical nodding for the process 400.

In an alternative implementation to the illsutrated implementation ofFIG. 4, the direction of the vertial nodding is selected to be up forphase 2 and the reverse (i.e., down) for phase 3.

FIG. 5 is a flow diagram illustrating a process 500 for authenticatingfor a VR system using a plurality of factors of authentication inaccordance with one implementation of the present disclosure. In oneimplementation, the process 500 collects a password entered into avirtual keyboard for a first factor of the plurality of factors ofauthentication, at block 510, wherein the password is entered by a userselecting a series of data including numbers and/or images on thevirtual keyboard displayed on a display of the VR system. Then, at block520, a biometric fingerprint is collected from movements of the VRsystem for a second factor of the plurality of factors ofauthentication.

FIG. 6 is a block diagram illustrating a system 600 for authenticatingfor a VR system using a plurality of factors of authentication inaccordance with one implementation of the present disclosure. In oneimplementation, the system 600 includes a first factor of authenticationcollector 610 and a second factor of authentication collector 620. Inone implementation, the first factor of authentication collector 610 isconfigured to collect a password entered into a virtual keyboard,wherein the password is entered by a user selecting a series of dataincluding numbers and/or images on the virtual keyboard displayed on adisplay of the VR system. In one implementation, the second factor ofauthentication collector 620 is configured to collect a biometricfingerprint from movements of the VR system.

The description herein of the disclosed implementations is provided toenable any person skilled in the art to make or use the presentdisclosure. Numerous modifications to these implementations would bereadily apparent to those skilled in the art, and the principals definedherein can be applied to other implementations without departing fromthe spirit or scope of the present disclosure. Thus, the presentdisclosure is not intended to be limited to the implementations shownherein but is to be accorded the widest scope consistent with theprincipal and novel features disclosed herein.

Various implementations of the present disclosure are realized inelectronic hardware, computer software, or combinations of thesetechnologies. Some implementations include one or more computer programsexecuted by one or more computing devices. In general, the computingdevice includes one or more processors, one or more data-storagecomponents (e.g., volatile or non-volatile memory modules and persistentoptical and magnetic storage devices, such as hard and floppy diskdrives, CD-ROM drives, and magnetic tape drives), one or more inputdevices (e.g., game controllers, mice and keyboards), and one or moreoutput devices (e.g., display devices).

The computer programs include executable code that is usually stored ina persistent storage medium and then copied into memory at run-time. Atleast one processor executes the code by retrieving program instructionsfrom memory in a prescribed order. When executing the program code, thecomputer receives data from the input and/or storage devices, performsoperations on the data, and then delivers the resulting data to theoutput and/or storage devices.

Those of skill in the art will appreciate that the various illustrativemodules and method steps described herein can be implemented aselectronic hardware, software, firmware or combinations of theforegoing. To clearly illustrate this interchangeability of hardware andsoftware, various illustrative modules and method steps have beendescribed herein generally in terms of their functionality. Whether suchfunctionality is implemented as hardware or software depends upon theparticular application and design constraints imposed on the overallsystem. Skilled persons can implement the described functionality invarying ways for each particular application, but such implementationdecisions should not be interpreted as causing a departure from thescope of the present disclosure. In addition, the grouping of functionswithin a module or step is for ease of description. Specific functionscan be moved from one module or step to another without departing fromthe present disclosure.

All features of each above-discussed example are not necessarilyrequired in a particular implementation of the present disclosure.Further, it is to be understood that the description and drawingspresented herein are representative of the subject matter which isbroadly contemplated by the present disclosure. It is further understoodthat the scope of the present disclosure fully encompasses otherimplementations that may become obvious to those skilled in the art andthat the scope of the present disclosure is accordingly limited bynothing other than the appended claims.

1. A method of authenticating for a virtual reality (VR) system using aplurality of factors of authentication, the method comprising:collecting a password entered into a virtual keyboard for a first factorof the plurality of factors of authentication, wherein the password isentered by a user selecting a series of data including numbers, letters,or images on the virtual keyboard displayed on a display of the VRsystem; and collecting a biometric fingerprint from movements of the VRsystem for a second factor of the plurality of factors ofauthentication.
 2. The method of claim 1, wherein the VR system is ahead-mounted display (HMD).
 3. The method of claim 1, further comprisingdisplaying the virtual keyboard on a half sphere in a fixed positionwithin the half sphere.
 4. The method of claim 3, wherein the virtualkeyboard is arranged as a random display of at least ten keys on thehalf sphere.
 5. The method of claim 1, wherein the password is enteredby gazing in a direction of a button on the virtual keyboard to selectthe button.
 6. The method of claim 5, wherein the selected button isvalidated by making a pre-defined acknowledging head gesture.
 7. Themethod of claim 6, wherein selection of the selected button is removedby making a pre-defined unselecting head gesture.
 8. The method of claim7, wherein the biometric fingerprint is collected from the movements ofthe VR system as reflected in the pre-defined acknowledging head gestureand the pre-defined unselecting head gesture.
 9. The method of claim 7,wherein collecting the biometric fingerprint comprises: measuringaccelerations of the pre-defined acknowledging head gesture and thepre-defined unselecting head gesture; and normalizing the accelerations.10. The method of claim 1, further comprising: comparing the collectedbiometric fingerprint to fingerprints in a fingerprint database; andidentifying the user when a fingerprint match is made.
 11. The method ofclaim 10, wherein the fingerprint match means that a similarity of thecollected biometric fingerprint and a reference fingerprint of thefingerprint match are within a defined boundary.
 12. A system ofauthenticating for a virtual reality (VR) system using a plurality offactors of authentication, the system comprising: a first factor ofauthentication collector configured to collect a password entered into avirtual keyboard, wherein the password is entered by a user selecting aseries of data including numbers or images on the virtual keyboarddisplayed on a display of the VR system; and a second factor ofauthentication collector configured to collect a biometric fingerprintfrom movements of the VR system.
 13. The system of claim 12, wherein theVR system is a head-mounted display (HMD).
 14. The system of claim 12,further comprising a projector configured to display the virtualkeyboard on a half sphere in a fixed position within the half sphere.15. The system of claim 14, wherein the virtual keyboard is arranged asa random display of at least ten keys on the half sphere.
 16. The systemof claim 12, wherein the second factor of authentication collector isconfigured to collect the biometric fingerprint from the movements ofthe VR system as reflected in pre-defined head gestures.
 17. The systemof claim 16, wherein the second factor of authentication collectorcollects the biometric fingerprint by measuring accelerations of thepre-defined head gestures.
 18. The system of claim 12, furthercomprising: a comparator configured to compare the collected biometricfingerprint to fingerprints in a fingerprint database; and an identifierconfigured to identify the user when a fingerprint match is made.
 19. Anapparatus for authenticating for a virtual reality (VR) system using aplurality of factors of authentication, the apparatus comprising: afirst means for collecting a password entered into a virtual keyboardfor a first factor of the plurality of factors of authentication,wherein the password is entered by a user selecting a series of dataincluding numbers or images on the virtual keyboard displayed on adisplay of the VR system; and a second means for collecting a biometricfingerprint from movements of the VR system for a second factor of theplurality of factors of authentication.
 20. The apparatus of claim 19,wherein the second means for collecting collects the biometricfingerprint from the movements of the VR system as reflected inpre-defined head gestures.
 21. The apparatus of claim 20, wherein thesecond means for collecting collects the biometric fingerprint bymeasuring accelerations of the pre-defined head gestures.